LOS ANGELES (AP) — Chris Brown was arrested Friday and will be held without bail on a warrant issued by probation officials in the latest legal entanglement for the RB singer who has struggled to put his 2009 attack on Rihanna behind him.

The warrant was issued by officials overseeing the singer’s sentence for the Rihanna case.

Sheriff’s officials said Brown was cooperative when he was arrested at a Malibu treatment facility where he had been staying.

Brown had been ordered to remain in rehab for treatment related to anger issues.

No other details on why the warrant was issued were released, and there was no immediate word on when the singer would appear in court.

An email sent to Brown’s attorney Mark Geragos was not immediately returned. A probation spokeswoman declined comment on what prompted Brown’s arrest.

Brown’s probation for the Rihanna assault had been scheduled to end this year, but a judge revoked it last year after Brown was arrested on a misdemeanor assault charge in Washington, D.C. That case is pending.

Superior Court Judge James R. Brandlin rejected a Los Angeles prosecutor’s request to send Brown to jail because of the Washington case, citing his progress in rehab.

In addition to getting treatment, the singer remained under strict orders to complete 1,000 of community labor this year. A probation report dated Feb. 26 stated that Brown had completed 250 hours and that he was being cooperative with probation officials.